1. Field
The inventive concept relates to a node device using a TV white space (TVWS), a TVWS network system, and a method for discovering a neighbor of a node device in a TVWS communication environment.
2. Description of Related Art
A smart grid network is an electrical grid infrastructure integrated with an IT communication system so as to provide efficient control and management. The smart grid network may be classified into three types of networks, i.e., a wide area network (WAN), a neighborhood area network (NAN), and a home area network (HAN). The HAN focuses small-scale data communication between electrical appliances or energy systems in a home. The HAN is also called as a last-mile smart grid (LMSG) or advanced metering infrastructure (AMI) network.
One of important characteristics of the AMI network for enabling the implementation of an accurate smart grid system is high reliability. In order to provide stable data communication, fiber and power line communication (PLC) networks are widely used in current AMI networks, but the scalability and flexibility of wired network systems are limited. In order to the limitation of the wired network systems, wireless communication protocols such as IEEE 802.15.4, IEEE 802.11, and Bluetooth are considered as solutions for AMI applications and network stack protocols.
Recently, a TV white space (TV white space) has come into the spotlight in relation to the AMI network. The TVWS is an idle portion of a digital TV (DTV) frequency band between 54 MHz and 862 MHz, and refers to a band accessible when the band is not used by TV and radio broadcasting. For various reasons of communication scope, reliability, stability, etc., an IEEE 802.15.4m TVWS protocol is considered in a smart grid network environment. The IEEE 802.15.4m TVWS protocol has an advantage in that it can build a stable AMI network, but has a problem in that a neighbor discovery delay caused when unsubscribed devices subscribe a network is rapidly increased as the number of communication channels increases.
An embodiment of the inventive concept is directed to a node device, a network system, and a method for discovering a neighbor of a node device in TV white space (TVWS) communication environment, which can reduce a neighbor discovery delay in the TVWS communication environment.